Wing of ilium
Encyclopedia
The wing of ilium
(or ala) is the large expanded portion which bounds the greater pelvis
laterally. It presents for examination two surfaces—an external and an internal—a crest, and two borders—an anterior and a posterior.
It is smooth, convex in front, deeply concave behind; bounded above by the crest, below by the upper border of the acetabulum
, in front and behind by the anterior and posterior borders.
This surface is crossed in an arched direction by three lines—the posterior
, anterior
, and inferior gluteal lines
.
The posterior gluteal line (superior curved line), the shortest of the three, begins at the crest, about 5 cm. in front of its posterior extremity; it is at first distinctly marked, but as it passes downward to the upper part of the greater sciatic notch
, where it ends, it becomes less distinct, and is often altogether lost.
Behind this line is a narrow semilunar surface, the upper part of which is rough and gives origin to a portion of the Glutæus maximus
; the lower part is smooth and has no muscular fibers attached to it.
The anterior gluteal line (middle curved line), the longest of the three, begins at the crest, about 4 cm. behind its anterior extremity, and, taking a curved direction downward and backward, ends at the upper part of the greater sciatic notch.
The space between the anterior and posterior gluteal lines and the crest is concave, and gives origin to the Glutæus medius
.
Near the middle of this line a nutrient foramen is often seen.
The inferior gluteal line (inferior curved line), the least distinct of the three, begins in front at the notch on the anterior border, and, curving backward and downward, ends near the middle of the greater sciatic notch.
The surface of bone included between the anterior and inferior gluteal lines is concave from above downward, convex from before backward, and gives origin to the Glutæus minimus
.
Between the inferior gluteal line and the upper part of the acetabulum is a rough, shallow groove, from which the reflected tendon of the Rectus femoris arises.
It presents a large, smooth, concave surface, called the iliac fossa, which gives origin to the Iliacus and is perforated at its inner part by a nutrient canal; and below this a smooth, rounded border, the arcuate line, which runs downward, forward, and medialward.
Behind the iliac fossa is a rough surface, divided into two portions, an anterior and a posterior. The anterior surface (auricular surface), so called from its resemblance in shape to the ear, is coated with cartilage in the fresh state, and articulates with a similar surface on the side of the sacrum.
The posterior portion, known as the iliac tuberosity, is elevated and rough, for the attachment of the posterior sacroiliac ligaments and for the origins of the Sacrospinalis and Multifidus.
Below and in front of the auricular surface is the preauricular sulcus, more commonly present and better marked in the female than in the male; to it is attached the pelvic portion of the anterior sacroiliac ligament
.
It is thinner at the center than at the extremities, and ends in the anterior and posterior superior iliac spines. The surface of the crest is broad, and divided into external and internal lips, and an intermediate line.
About 5 cm. behind the anterior superior iliac spine
there is a prominent tubercle
on the outer lip.
To the external lip are attached the Tensor fasciæ latæ, Obliquus externus abdominis, and Latissimus dorsi, and along its whole length the fascia lata
; to the intermediate line the Obliquus internus abdominis; to the internal lip, the fascia iliaca, the Transversus abdominis, Quadratus lumborum, Sacrospinalis, and Iliacus.
Of these, the uppermost, situated at the junction of the crest and anterior border, is called the anterior superior iliac spine
; its outer border gives attachment to the fascia lata
, and the Tensor fasciæ latæ, its inner border, to the Iliacus; while its extremity affords attachment to the inguinal ligament
and gives origin to the sartorius
Beneath this eminence is a notch from which the Sartorius takes origin and across which the lateral femoral cutaneous nerve passes.
Below the notch is the anterior inferior iliac spine, which ends in the upper lip of the acetabulum; it gives attachment to the straight tendon of the Rectus femoris and to the iliofemoral ligament
of the hip-joint.
Medial to the anterior inferior spine is a broad, shallow groove, over which the Iliacus and Psoas major pass.
This groove is bounded medially by an eminence, the iliopectineal eminence, which marks the point of union of the ilium
and pubis
.
and the posterior inferior iliac spine
.
The former serves for the attachment of the oblique portion of the posterior sacroiliac ligaments and the Multifidus; the latter corresponds with the posterior extremity of the auricular surface.
Below the posterior inferior spine is a deep notch, the greater sciatic notch.
Ilium (bone)
The ilium is the uppermost and largest bone of the pelvis, and appears in most vertebrates including mammals and birds, but not bony fish. All reptiles have an ilium except snakes, although some snake species have a tiny bone which is considered to be an ilium.The name comes from the Latin ,...
(or ala) is the large expanded portion which bounds the greater pelvis
Greater pelvis
The greater pelvis is a portion of the cavity surrounded by the skeleton of the pelvis, situated above and in front of the pelvic brim...
laterally. It presents for examination two surfaces—an external and an internal—a crest, and two borders—an anterior and a posterior.
External surface
The external surface, known as the dorsum ilii, is directed backward and lateralward behind, and downward and lateralward in front.It is smooth, convex in front, deeply concave behind; bounded above by the crest, below by the upper border of the acetabulum
Acetabulum
The acetabulum is a concave surface of the pelvis. The head of the femur meets with the pelvis at the acetabulum, forming the hip joint.-Structure:...
, in front and behind by the anterior and posterior borders.
This surface is crossed in an arched direction by three lines—the posterior
Posterior gluteal line
The posterior gluteal line , the shortest of the three gluteal lines, begins at the iliac crest, about 5 cm in front of its posterior extremity; it is at first distinctly marked, but as it passes downward to the upper part of the greater sciatic notch, where it ends, it becomes less distinct, and...
, anterior
Anterior gluteal line
The anterior gluteal line refers to a bone in the human pelvis. It is the longest of the three gluteal lines, begins at the crest, about 4 cm...
, and inferior gluteal lines
Inferior gluteal line
The inferior gluteal line , the least distinct of the three gluteal lines, begins in front at the notch on the anterior border, and, curving backward and downward, ends near the middle of the greater sciatic notch....
.
The posterior gluteal line (superior curved line), the shortest of the three, begins at the crest, about 5 cm. in front of its posterior extremity; it is at first distinctly marked, but as it passes downward to the upper part of the greater sciatic notch
Greater sciatic notch
Above the ischial spine is a large notch, the greater sciatic notch, converted into a foramen by the sacrospinous ligament.It transmits the Piriformis, the superior and inferior gluteal vessels and nerves, the sciatic and posterior femoral cutaneous nerves, the internal pudendal vessels, and the...
, where it ends, it becomes less distinct, and is often altogether lost.
Behind this line is a narrow semilunar surface, the upper part of which is rough and gives origin to a portion of the Glutæus maximus
Gluteus maximus muscle
The gluteus maximus is the largest and most superficial of the three gluteal muscles...
; the lower part is smooth and has no muscular fibers attached to it.
The anterior gluteal line (middle curved line), the longest of the three, begins at the crest, about 4 cm. behind its anterior extremity, and, taking a curved direction downward and backward, ends at the upper part of the greater sciatic notch.
The space between the anterior and posterior gluteal lines and the crest is concave, and gives origin to the Glutæus medius
Gluteus medius muscle
The gluteus medius , one of the three gluteal muscles, is a broad, thick, radiating muscle, situated on the outer surface of the pelvis....
.
Near the middle of this line a nutrient foramen is often seen.
The inferior gluteal line (inferior curved line), the least distinct of the three, begins in front at the notch on the anterior border, and, curving backward and downward, ends near the middle of the greater sciatic notch.
The surface of bone included between the anterior and inferior gluteal lines is concave from above downward, convex from before backward, and gives origin to the Glutæus minimus
Gluteus minimus muscle
The gluteus minimus , the smallest of the three gluteal muscles, is situated immediately beneath the gluteus medius.-Origin and insertion:...
.
Between the inferior gluteal line and the upper part of the acetabulum is a rough, shallow groove, from which the reflected tendon of the Rectus femoris arises.
Internal surface of the ala
The internal surface of the ala is bounded above by the crest, below, by the arcuate line; in front and behind, by the anterior and posterior borders.It presents a large, smooth, concave surface, called the iliac fossa, which gives origin to the Iliacus and is perforated at its inner part by a nutrient canal; and below this a smooth, rounded border, the arcuate line, which runs downward, forward, and medialward.
Behind the iliac fossa is a rough surface, divided into two portions, an anterior and a posterior. The anterior surface (auricular surface), so called from its resemblance in shape to the ear, is coated with cartilage in the fresh state, and articulates with a similar surface on the side of the sacrum.
The posterior portion, known as the iliac tuberosity, is elevated and rough, for the attachment of the posterior sacroiliac ligaments and for the origins of the Sacrospinalis and Multifidus.
Below and in front of the auricular surface is the preauricular sulcus, more commonly present and better marked in the female than in the male; to it is attached the pelvic portion of the anterior sacroiliac ligament
Anterior sacroiliac ligament
The anterior sacroiliac ligament consists of numerous thin bands, which connect the anterior surface of the lateral part of the sacrum to the margin of the auricular surface of the ilium and to the preauricular sulcus....
.
Crest of the ilium
The crest of the ilium is convex in its general outline but is sinuously curved, being concave inward in front, concave outward behind.It is thinner at the center than at the extremities, and ends in the anterior and posterior superior iliac spines. The surface of the crest is broad, and divided into external and internal lips, and an intermediate line.
About 5 cm. behind the anterior superior iliac spine
Anterior superior iliac spine
The anterior superior iliac spine is an important landmark of surface anatomy. It refers to the anterior extremity of the iliac crest of the pelvis, which provides attachment for the inguinal ligament, and the sartorius muscle...
there is a prominent tubercle
Iliac tubercle
The iliac tubercle is located approximately posterior to the anterior superior iliac spine on the iliac crest in humans. The transverse plane that includes each of the tubercles is called the transtubercular plane. The origin of the iliotibial tract is the iliac tubercle...
on the outer lip.
To the external lip are attached the Tensor fasciæ latæ, Obliquus externus abdominis, and Latissimus dorsi, and along its whole length the fascia lata
Fascia lata
-Thickness:It is an investment for the whole of the thigh, but varies in thickness in different parts.Thus, it is thicker in the upper and lateral part of the thigh, where it receives a fibrous expansion from the Glutæus maximus, and where the Tensor fasciæ latæ is inserted between its layers; it...
; to the intermediate line the Obliquus internus abdominis; to the internal lip, the fascia iliaca, the Transversus abdominis, Quadratus lumborum, Sacrospinalis, and Iliacus.
Anterior border of the ala
The anterior border of the ala is concave. It presents two projections, separated by a notch.Of these, the uppermost, situated at the junction of the crest and anterior border, is called the anterior superior iliac spine
Anterior superior iliac spine
The anterior superior iliac spine is an important landmark of surface anatomy. It refers to the anterior extremity of the iliac crest of the pelvis, which provides attachment for the inguinal ligament, and the sartorius muscle...
; its outer border gives attachment to the fascia lata
Fascia lata
-Thickness:It is an investment for the whole of the thigh, but varies in thickness in different parts.Thus, it is thicker in the upper and lateral part of the thigh, where it receives a fibrous expansion from the Glutæus maximus, and where the Tensor fasciæ latæ is inserted between its layers; it...
, and the Tensor fasciæ latæ, its inner border, to the Iliacus; while its extremity affords attachment to the inguinal ligament
Inguinal ligament
The inguinal ligament is a band running from the pubic tubercle to the anterior superior iliac spine. Its anatomy is very important for operating on hernia patients.-Anatomy:...
and gives origin to the sartorius
Sartorius muscle
The Sartorius muscle – the longest muscle in the human body – is a long thin muscle that runs down the length of the thigh. Its upper portion forms the lateral border of the femoral triangle.-Origin and insertion:...
Beneath this eminence is a notch from which the Sartorius takes origin and across which the lateral femoral cutaneous nerve passes.
Below the notch is the anterior inferior iliac spine, which ends in the upper lip of the acetabulum; it gives attachment to the straight tendon of the Rectus femoris and to the iliofemoral ligament
Iliofemoral ligament
The iliofemoral ligament is a ligament of the hip joint which extends from the ilium to the femur in front of the joint. It is also referred to as the Y-ligament or the ligament of Bigelow, and any combinations of these names....
of the hip-joint.
Medial to the anterior inferior spine is a broad, shallow groove, over which the Iliacus and Psoas major pass.
This groove is bounded medially by an eminence, the iliopectineal eminence, which marks the point of union of the ilium
Ilium (bone)
The ilium is the uppermost and largest bone of the pelvis, and appears in most vertebrates including mammals and birds, but not bony fish. All reptiles have an ilium except snakes, although some snake species have a tiny bone which is considered to be an ilium.The name comes from the Latin ,...
and pubis
Pubis (bone)
In vertebrates, the pubic bone is the ventral and anterior of the three principal bones composing either half of the pelvis.It is covered by a layer of fat, which is covered by the mons pubis....
.
Posterior border of the ala
The posterior border of the ala, shorter than the anterior, also presents two projections separated by a notch, the posterior superior iliac spinePosterior superior iliac spine
The posterior border of the ala, shorter than the anterior, also presents two projections separated by a notch, the posterior superior iliac spine and the posterior inferior iliac spine. The posterior superior iliac spine serves for the attachment of the oblique portion of the posterior sacroiliac...
and the posterior inferior iliac spine
Posterior inferior iliac spine
The posterior border of the ala, shorter than the anterior, also presents two projections separated by a notch, the posterior superior iliac spine and the posterior inferior iliac spine. The posterior inferior iliac spine corresponds with the posterior extremity of the auricular surface....
.
The former serves for the attachment of the oblique portion of the posterior sacroiliac ligaments and the Multifidus; the latter corresponds with the posterior extremity of the auricular surface.
Below the posterior inferior spine is a deep notch, the greater sciatic notch.
